Prognostic value and immune landscapes of cuproptosis-related lncRNAs in esophageal squamous cell carcinoma

BACKGROUND

Precisely forecasting the prognosis of esophageal squamous cell carcinoma (ESCC) patients is a formidable challenge. Cuproptosis has been implicated in ESCC pathogenesis; however, the prognostic value of cuproptosis-associated long noncoding RNAs (CuRLs) in ESCC is unclear.

METHODS

Transcriptomic and clinical data related to ESCC were sourced from The Cancer Genome Atlas (TCGA). Using coexpression and Cox regression analysis to identify prognostically significant CuRLs, a prognostic signature was created. Nomogram models were established by incorporating the risk score and clinical characteristics. Tumor Immune Dysfunction and Rejection (TIDE) scores were derived by conducting an immune landscape analysis and evaluating the tumor mutational burden (TMB). Drug sensitivity analysis was performed to explore the underlying molecular mechanisms and guide clinical dosing.

RESULTS

Our risk score based on 5 CuRLs accurately predicted poorer prognosis in high-risk ESCC patients across almost all subgroups. The nomogram that included the risk score provided more precise prognostic predictions. Immune pathways, such as the B-cell receptor signaling pathway, were enriched in the datasets from high-risk patients. High TMB in high-risk patients indicated a relatively poor prognosis. High-risk patients with lower TIDE scores were found to benefit more from immunotherapy. High-risk patients exhibited greater responsiveness to Nilotinib, BI-2536, P22077, Zoledronate, and Fulvestrant, as revealed by drug sensitivity analysis. Real-time PCR validation demonstrated significant differential expression of four CuRLs between ESCC and normal cell lines.

CONCLUSIONS

The above risk score and nomogram can accurately predict prognosis in ESCC patients and provide guidance for chemotherapy and immunotherapy.

[Effect of Porphyromonas gingivalis infection on IFNGR1 palmitoylation in esophageal cancer cells]

OBJECTIVE

To investigate the effect of Porphyromonas gingivalis (Pg) infection on IFNGR1 palmitoylation and biological behaviors of esophageal squamous cell carcinoma (ESCC) cells and the clinical implications.

METHODS

The expression levels of IFNGR1 protein in ESCC cell lines KYSE30 and KYSE70 were detected using Western blotting at 24 and 48 h after Pg infection, and 2-BP was used to detect IFNGR1 palmitoylation in the cells. KYSE70 cells with wild-type IFNGR1 (IFNGR1-WT cells) and with IFNGR1-C122A palmitoylation site mutation induced by site-specific mutagenesis (IFNGR1-C122A cells) were both infected with Pg, and the changes in palmitoylation of IFNGR1-C122A were analyzed using immunofluorescence and Click-iT assays. The changes in proliferation, migration and invasion ability of the infected cells were evaluated using plate cloning assay, scratch assay and Transwell assay, and IFNGR1 co-localization with lysosomal marker LAMP2 was dected using immunofluorescence assay. Immunohistochemistry was used to detect Pg infection and IFNGR1 protein expression in 50 ESCC tissues, and their correlation with the clinicopathological characteristics and survival outcomes of the patients was analyzed.

RESULTS

Pg infection down-regulated the protein expression of IFNGR1 in ESCC and promoted IFNGR1 palmitoylation at site 122. In IFNGR1-WT cells, Pg infection significantly enhanced cell proliferation, migration and invasion (P < 0.05). Similarly, Pg also significantly promoted proliferation, migration and invasion of IFNGR1-C122A cells, but to a lesser extent as compared with the wild-type cells (P < 0.05). Immunofluorescence assay showed that Pg and ZDHHC3 promoted IFNGR1 degradation within the lysosome. Immunohistochemical studies of the ESCC tissue samples showed a negative correlation between IFNGR1 and Pg expression, and a reduced IFNGR1 expression was correlated with a poorer survival outcome of the patient.

CONCLUSION

Pg infection enhances IFNGR1 palmitoylation to promote progression of ESCC, and elimination of Pg and inhibiting IFNGR1 palmitoylation may effectively control ESCC progression.

A tricarboxylic acid cycle-based machine learning model to select effective drug targets for the treatment of esophageal squamous cell carcinoma

Background: The tricarboxylic acid cycle (TCA cycle) is an important metabolic pathway and closely related to tumor development. However, its role in the development of esophageal squamous cell carcinoma (ESCC) has not been fully investigated. Methods: The RNA expression profiles of ESCC samples were retrieved from the TCGA database, and the GSE53624 dataset was additionally downloaded from the GEO database as the validation cohort. Furthermore, the single cell sequencing dataset GSE160269 was downloaded. TCA cycle-related genes were obtained from the MSigDB database. A risk score model for ESCC based on the key genes of the TCA cycle was built, and its predictive performance was evaluated. The association of the model with immune infiltration and chemoresistance were analyzed using the TIMER database, the R package "oncoPredict" score, TIDE score and so on. Finally, the role of the key gene CTTN was validated through gene knockdown and functional assays. Results: A total of 38 clusters of 8 cell types were identified using the single-cell sequencing data. The cells were divided into two groups according to the TCA cycle score, and 617 genes were identified that were most likely to influence the TCA cycle. By intersecting 976 key genes of the TCA cycle with the results of WGCNA, 57 genes significantly associated with the TCA cycle were further identified, of which 8 were screened through Cox regression and Lasso regression to construct the risk score model. The risk score was a good predictor of prognosis across subgroups of age, N, M classification and TNM stage. Furthermore, BI-2536, camptothecin and NU7441 were identified as possible drug candidates in the high-risk group. The high-risk score was associated with decreased immune infiltration in ESCC, and the low-risk group had better immunogenicity. In addition, we also evaluated the relationship between risk scores and immunotherapy response rates. Functional assays showed that CTTN may affect the proliferation and invasion of ESCC cells through the EMT pathway. Conclusion: We constructed a predictive model for ESCC based on TCA cycle-associated genes, which achieved good prognostic stratification. The model are likely associated with the regulation of tumor immunity in ESCC.

Single-Cell Transcriptomic Analysis of Primary and Metastatic Tumor Ecosystems in Esophageal Squamous Cell Carcinoma

Lymph node metastasis, the leading cause of mortality in esophageal squamous carcinoma (ESCC) with a highly complex tumor microenvironment, remains underexplored. Here, the transcriptomes of 85 263 single cells are analyzed from four ESCC patients with lymph node metastases. Strikingly, it is observed that the metastatic microenvironment undergoes the emergence or expansion of interferon induced IFIT3+ T, B cells, and immunosuppressive cells such as APOC1+ APOE+ macrophages and myofibroblasts with highly expression of immunoglobulin genes (IGKC) and extracellular matrix component and matrix metallopeptidase genes. A poor-prognostic epithelial-immune dual expression program regulating immune effector processes, whose activity is significantly enhanced in metastatic malignant epithelial cells and enriched in CD74+ CXCR4+ and major histocompatibility complex (MHC) class II genes upregulated malignant epithelia cells is discovered. Comparing with primary tumor, differential intercellular communications of metastatic ESCC microenvironment are revealed and furtherly validated via multiplexed immunofluorescence and immunohistochemistry staining, which mainly rely on the crosstalk of APOC1+ APOE+ macrophages with tumor and stromal cell. The data highlight potential molecular mechanisms that shape the lymph-node metastatic microenvironment and may inform drug discovery and the development of new strategies to target these prometastatic nontumor components for inhibiting tumor growth and overcoming metastasis to improve clinical outcomes.

A Comparative Analysis of the Gene Expression Profiles of Small Cell Esophageal Carcinoma, Small Cell Lung Cancer, and Esophageal Adeno/Squamous Carcinoma

Purpose/objectives: Primary small cell esophageal carcinoma (SCEC) is a rare malignancy without an established treatment strategy. This study investigated the gene expression profile of SCEC and compared it with the expression profiles of small cell lung cancer (SCLC) and esophageal adeno/squamous carcinoma (EAC/ESCC). Materials/methods: All patients with SCEC, SCLC, and EAC/ESCC in the Surveillance, Epidemiology, and End Results (SEER) database 1973-2014 were included. Overall survival (OS) and prognostic analysis were conducted. De novo expression array analysis was performed on three pairs of frozen primary SCEC tissues and the corresponding normal samples from the institutional tissue bank using the Affymetrix HG U133 plus 2.0 Array. These data were complemented with public domain expression data sets from the Gene Expression Omnibus (GEO) repository using the same working platforms, which included primary SCLC, EAC/ESCC, and normal lung/esophagus specimens (series GSE30219 and GSE26886). After individual normalization, the primary tumors were submitted to statistical analysis (GeneSpring GX 13.0) to identify the differentially expressed genes (DEGs) relative to their paired normal tissues. Enrichments of genes categorized by function and gene interactions were analyzed by DAVID 6.8 and STRING 11.0, respectively. Results: The clinical outcomes of the patients with SCEC were significantly more worse than those with EAC/ESCC and SCLC in the SEER database. SCEC had more DEGs in common with SCLC than EAC/ESCC [829 vs. 450; false discovery rate (FDR) < 0.01; and fold change ≥2], leading to a stronger correlation between SCEC and SCLC (Pearson's correlation coefficient was 0.60 for SCEC vs. SCLC, 0.51 or 0.45 for SCEC vs. ESCC or EAC, and the coefficient was 0.73 for ESCC vs. EAC). Similar findings were obtained by principal component analysis (PCA) using all DEGs retrieved from these four groups. Functional annotation showed that a higher proportion of pathways and biological processes were common between SCEC and SCLC and were associated with the cell cycle (mitosis), DNA replication, telomere maintenance, DNA repair, and P53 and RB pathways (Benjamini p < 0.05). Compared with EAC/ESCC, SCEC shared more co-upregulated DEGs coding for the aforementioned common pathways with SCLC (584 vs. 155). In addition, SCEC and SCLC were found to have possessed overlapping gene-interactive networks, with centromere protein F (CENPF), never in mitosis gene A-related kinase 2 ( NEK2), kinesin family member 11 (KIF11), thymopoietin (TMPO), and forkhead box protein M1 (FOXM1) as common skeletons centered by gene regulatory network (NUF2). Conclusions: This study is the first attempt to examine the genomic signatures of SCEC at the transcriptomic level and compare the expression profiles between SCEC, SCLC, and EAC/ESCC. Our preliminary data indicate that SCEC and SCLC display notably similar patterns of gene expression for mitosis and DNA repair. Further validation studies are warranted.

Silencing UHRF1 Enhances Radiosensitivity of Esophageal Squamous Cell Carcinoma by Inhibiting the PI3K/Akt/mTOR Signaling Pathway

Purpose

Resistance to radiotherapy results in a high treatment failure rate for locally advanced esophageal squamous cell carcinoma (ESCC). Ubiquitin-like with plant homeodomain and ring-finger domains 1 (UHRF1), is associated with poor prognosis in ESCC. The present study aims to characterize the effect of UHRF1 silencing on the radiosensitivity of ESCC and its potential mechanism.

Methods

Both in vitro and in vivo experiments were conducted to observe the effects of UHRF1 silencing on the radiosensitivity of ESCC. The effects of UHRF1 silencing on the apoptosis of ESCC cells were assessed by flow cytometry. The expression of apoptosis-related factors (caspase-3 and Bcl-2), PI3K/Akt/mTOR signaling pathway-related factors (PTEN, p-Akt and Akt, p-mTOR and mTOR), and DNMT1 were measured via Western blot, and the status of PTEN methylation was detected by methylation-specific PCR. Immunohistochemistry was used to detect the expressions of PTEN, p-AKT, and p-mTOR in xenograft tumor tissues.

Results

In vitro and in vivo experiments showed that UHRF1 knock-down inhibited ESCC cell growth and enhanced their radiosensitivity. shUHRF1 combined with radiation significantly increased ESCC cell apoptosis. Meanwhile, it activated the expression of caspase-3 and inhibited the expression of Bcl-2. shUHRF1 inhibited the expression of DNMT1 and reduced the methylation of PTEN, and then upregulated the expression of PTEN to inhibit the PI3K/Akt/mTOR signaling pathway. On the contrary, the PI3K/Akt/mTOR signaling pathway can be activated by upregulation of UHRF1.

Conclusion

Our findings provide a theoretical basis for UHRF1 as a target to improve the radiosensitivity of ESCC.

Nivolumab induced hyperprogressive disease in advanced esophageal squamous cell carcinoma

Immune checkpoint inhibitors have demonstrated promising efficacy and tolerable safety for advanced malignancies. However, a proportion of patients who had received immunotherapy may experience hyperprogressive disease and a resultant poor prognosis. Here, we report a patient with advanced esophageal squamous carcinoma who developed hyperprogressive disease shortly after immunotherapy. This patient received nivolumab after multiple lines of treatment, including chemotherapy, radiotherapy, and antiangiogenic therapy. Through the comprehensive analysis of NGS results, we concluded that the PI3K/AKT signaling pathway might be associated with hyperprogressive disease after immunotherapy. Additionally, potential mechanisms underlying hyperprogressive disease after immunotherapy reported in other malignant tumors were also summarized.

GEFT protein expression in digestive tract malignant tumors and its clinical significance

Guanine nucleotide exchange factor T (GEFT), a member of the Rho guanine nucleotide exchange factor family, is expressed in a variety of tumors. In the present study, the expression and clinical significance of GEFT in malignant digestive tract tumors was assessed. Tumor and adjacent control samples from 180 patients were tested. Positive GEFT expression rates were 80, 83.33 and 86.67% in esophageal squamous carcinoma (ESCC), gastric carcinoma (GC) and colorectal cancer (CRC), respectively. GEFT expression was associated with diffuse type carcinoma according to the Lauren classification (χ²=12.525, P=0.002) and tumor-node-metastasis (TNM) stages III/IV (χ²=4.033, P=0.045) in GC, and with vessel carcinoma embolus (χ²=7.890, P=0.005) and lymph node metastasis (χ²=5.455, P=0.020) in CRC, but was not associated with other clinicopathological parameters. Patients with high levels of GEFT protein expression had a less favorable outcome compared with patients with low levels of GEFT expression in patients with CRC (χ²=3.876, P=0.049). However, a significant association was not found between GEFT expression and overall survival in patients with ESCC (χ²=0.040, P=0.842) or GC (χ²=0.501, P=0.479). The rate of human epidermal growth factor receptor 2 upregulation in patients with GC was 13.33% and it was associated with nerve invasion (χ²=4.005, P=0.045) and TNM stages III/IV (χ²=5.600, P=0.018). Mismatch repair protein (MMRP) defect was observed in six cases, and the KRAS mutation rate was 26.67% in patients with CRC. GEFT expression was significantly correlated with MMRP (r=-0.285, P=0.027) and KRAS mutation in patients with CRC (r=0.697, P<0.001). These findings revealed frequent GEFT upregulation in malignant digestive tract tumors, which may have promoted tumor development. GEFT expression in CRC may be associated with microsatellite instability and KRAS mutation status, suggesting that GEFT may be a potential therapeutic target for patients with CRC.

Changing expression profiles of lncRNAs, circRNAs and mRNAs in esophageal squamous carcinoma

Abundant evidence indicates that long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) serve important roles in tumorigenesis and tumour progression. However, their diagnostic and treatment value for esophageal squamous carcinoma (ESCC) remains unknown. A microarray (SBC human ceRNA array V1.0) was performed to assess the expression profiles and biological functions of lncRNAs, circRNAs and mRNAs in ESCC and para-cancerous tissues from three patients. Microarray data were validated by reverse transcription-quantitative polymerase chain reaction for a group of genes. A number of lncRNA-microRNAs (miRNA) and circRNA-miRNA-mRNA networks were constructed. Bioinformatics tools, including gene ontology and Kyoto Encyclopedia of Genes and Genomes biological pathway analyses, were used to predict the functions of differentially expressed lncRNAs, circRNAs and potentially co-expressed target genes. The results revealed that compared with the expression levels of para-cancerous tissues, 1,384 lncRNAs, 2,046 circRNAs and 936 mRNAs were frequently altered in ESCC tissues. Co-expression networks of lncRNAs-miRNAs-circRNAs-mRNAs were constructed based on the correlation analyses among the differentially expressed RNAs. Furthermore, using bioinformatics methods, correlation expression networks were constructed that included cis- and trans-regulatory elements. Therefore, these results suggest that lncRNAs and circRNAs may be involved in the pathogenesis and development of ESCC. These findings provide a novel and systematic perspective on the potential function of noncoding RNAs in ESCC.

Luteolin inhibits cell proliferation and induces cell apoptosis via down-regulation of mitochondrial membrane potential in esophageal carcinoma cells EC1 and KYSE450

In current study, we investigated the anti-tumor effect of luteolin in human ESCC cell lines in vitro and in vivo and tried to explore the potential mechanisms. Results from flow cytometry showed that luteolin could induce apoptosis and caspase-3 activation and induce cell cycle arrest at G2/M phase in a dose- and time-dependent manner in EC1 and KYSE450 cells. JC-1 test results showed that membrane potential of mitochondria after luteolin treatment was down-regulated and this was an indicator for intrinsic apoptosis. Western Blot results showed the expression of cell cycle regulatory protein p21 and p53 increased and three apoptosis related proteins that participate in mitochondrial apoptotic pathway, namely, Bim, CYT-c and cPARP, also increased in luteolin treated cells compared with control groups. We further confirmed that luteolin could significantly inhibit the growth of ESCC tumors in xenograft mouse models and no evidence of systemic toxicity was observed. Our results suggest that luteolin can induce cell apoptosis and cell cycle arrest in G2/M phase through mitochondrial pathway in EC1 and KYSE450 cell lines and proper utilization of luteolin might be a practical approach in ESCC chemotherapy.

Elevated expression of the IGF2 mRNA binding protein 2 (IGF2BP2/IMP2) is linked to short survival and metastasis in esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) represents the sixth leading cause of cancer-related deaths and develops in Barret's esophagus affected tissues. The IGF2 mRNA binding protein IMP2/IGF2BP2/p62 was originally identified as an autoantigen in hepatocellular carcinoma. Aim of this study was to investigate the expression and prognostic role of IMP2 in EAC. Human EAC and Barret's esophagus tissue showed overexpression of IMP2, particularly in tumors of increased size and in metastatic tissues. Molecular classification based on published gene signatures of esophageal cancer revealed a specific subtype, in which the expression of IMP2 is high. According to GO and KEGG pathway analyses, genes showing highly correlated expression with IMP2 are associated with growth, proliferation, metabolism, inflammation, and cancerous processes. Clustering of EAC samples according to published survival marker genes strongly suggests that IMP2 overexpressing samples show poor survival. Finally, IMP2 expression correlated with short survival in patients with EAC or esophageal squamous carcinoma. Our data indicate that IMP2 might be a useful prognostic marker for Barret's esophagus and EAC.

Network-Based Differential Analysis to Identify Molecular Features of Tumorigenesis for Esophageal Squamous Carcinoma

Esophageal cancer has a poor prognosis and high mortality rate across the world. The diagnosis and treatment of esophageal cancer are hindered by the limited knowledge about the pathogenesis mechanisms of esophageal cancer. Esophageal cancer has two major subtypes, squamous and adenocarcinoma. In this work, we proposed a method to select candidate biomarkers of esophageal squamous carcinoma based on the topological differential analysis between the gene–gene interaction networks for esophageal squamous carcinoma and normal cells. We established the gene–gene interaction networks for esophageal squamous carcinoma and normal based on the correlation of genes. For each gene, we firstly calculated and compared five centrality measures, which could reflect the topological property of a network. According to five centrality measures, the genes with large differences between the two networks were regarded as candidate biomarkers for esophageal squamous carcinoma. A total of 21 candidate biomarkers were identified for esophageal squamous carcinoma, and seven of them have been confirmed to be biomarkers of esophageal-12 squamous carcinoma by previous research. In addition, six genes (RBPMS2, PDK4, IGK, SBSN, IFIT3 and HSPB6) were likely to be the biomarkers of tumorigenesis for esophageal squamous carcinoma due to the fact that the biological processes in which they participate are closely related with the development of esophageal squamous carcinoma. Statistical analysis indicates that effectiveness of the detected biomarkers of esophageal squamous carcinoma. The proposed method could be extended to other complex diseases for detecting the molecular features of pathopoiesis and targets for targeted therapy.

CCR7 enhances the angiogenic capacity of esophageal squamous carcinoma cells in vitro via activation of the NF-κB/VEGF signaling pathway

High levels of angiogenesis are associated with poor prognosis and a highly invasive phenotype in esophageal squamous carcinoma. C-C chemokine receptor type 7 (CCR7) is overexpressed in multiple tumor types and has been suggested to act as an oncogene and pro-angiogenic factor. This study aimed to elucidate the effect of CCR7 on the angiogenic capacity of esophageal squamous carcinoma cells in vitro. Expression of CCR7 in esophageal squamous carcinoma cell lines and normal human esophageal epithelial cell line was examined by western blotting and quantitative real-time PCR. CCR7 was stably overexpressed or transiently knocked down in esophageal squamous carcinoma cell lines. Overexpressing CCR7 enhanced the capacity of esophageal squamous carcinoma cell conditioned media to induce human umbilical vein endothelial cells (HUVEC) proliferation and migration and neovascularization in the chicken chorioallantoic membrane (CAM) assay. While silencing CCR7 caused an opposite outcome. Moreover, we demonstrated that CCR7 activated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling and regulated its targets, including vascular endothelial growth factor A (VEGF-A), VEGF-C, tumor necrosis factor-α (TNFα), interleukin (IL)-6, IL-8 and transforming growth factor-β (TGF-β) expression. Additionally, CCR7 down-regulation reduced tumor volume and weight in xenograft mouse model, and significantly decreased NF-κB signaling pathway. This study suggests that CCR7 plays an important pro-angiogenic role in esophageal squamous carcinoma via a mechanism linked to activation of the NF-κB pathway; CCR7 may represent a potential target for anti-angiogenic therapy in esophageal squamous carcinoma.

Significance of Upper Mediastinal Lymph Node Dissection with Video-Assisted Thoracic Surgery in the Treatment of Middle Thoracic Esophageal Carcinoma

BACKGROUND

The aim of this study was to explore the significance of upper mediastinal lymph node dissection performed by video-assisted thoracic surgery in the treatment of middle thoracic esophageal carcinoma.

MATERIALS AND METHODS

The clinical and pathological data from 128 patients with middle thoracic esophageal carcinoma who underwent surgery from January 2013 to December 2015 using a right chest-abdomen-neck approach combined with thoracoscopy and laparoscopy in the Jieyang People's Hospital of Huangdong province were analyzed retrospectively.

RESULTS

The lymph node metastasis rates of the thoracic left para-recurrent laryngeal nerve (1, 2, and 4L zones) and right para-recurrent laryngeal nerve (1R zone) were 30.47% and 28.12% in 128 cases, respectively. The metastasis rates of the 2R, 4R, and 5 zones were 4.69%, 3.91%, and 5.47%, respectively.

CONCLUSIONS

The upper mediastinal region was the most common location for lymph node metastasis from middle thoracic esophageal carcinoma, and upper mediastinal lymph node dissection performed by video-assisted thoracic surgery was safe and complete. It also reduced the risk of para-recurrent laryngeal nerve injury, residual tumor, and the postoperative recurrence rate.

Up regulation of the long non-coding RNA NEAT1 promotes esophageal squamous cell carcinoma cell progression and correlates with poor prognosis

Dysregulation of NEAT1 plays critical oncogenic roles and facilitates tumorigenesis on various human tumor entities. However, little information is available about the expression pattern of NEAT1 in esophageal squamous cell carcinoma (ESCC). The contributions of this lncRNA to tumorigenesis and progression of ESCC aslo remains unclear. By performing quantitative real-time polymerase chain reaction (qRT-PCR) in 96 cases of ESCC, we found that the expression of NEAT1 was higher in ESCC tissues and cells compared with the normal counterparts. Pearson analysis showed that elevated NEAT1 levels were extraordinarily correlated with the tumor size (P=0.026), lymph node metastasis (P=0.035) and clinical stage (P=0.004). Moreover, Kaplan-Meier curves with the log-rank test showed that higher expression of NEAT1 led to a significantly poorer survival and multivariate Cox proportional hazards analysis revealed that NEAT1 was an independent risk factor of overall survival (OS). We also assessed the function of NEAT1 in vitro by gain-/loss-of-function studies. Results showed that enhanced expression of NEAT1 stimulated the proliferation of ESCC cells, and promoted their ability of forming foci, migration, and invasion. Conversely, knockdown of NEAT1 showed the opposite effect. Overall, our study indicated that the inappropriate activation of NEAT1 predicts poor prognosis and has a crucial regulatory role in in ESCC. Targeting NEAT1 could be a novel therapeutic choice for treating ESCC patients.

Impact of body mass index on survival of esophageal squamous carcinoma patients in southern China

BACKGROUND

Although high body mass index (BMI) increases risk for developing esophageal adenocarcinoma (EAC), the prognostic influence of BMI is unknown in esophageal squamous carcinoma.

METHODS

BMI was calculated using measured height and weight at the first diagnosis and categorized as overweight (25 to 29.9 kg/m(2)), normal (18.5 to 24.9 kg/m(2)) or underweight (<18.5 kg/m(2)). Survival was compared by using the log-rank test on the Kaplan-Meier life table. Multivariate Cox regression analysis was used to evaluate whether BMI was an independent prognostic factor for disease-specific survival (DSS).

RESULTS

Among 1,176 esophageal squamous carcinoma patients, 146 (12.4%) were categorized as overweight, and 277 (23.6%) underweight. More patients in the underweight group had anemia (P=0.001), weight loss (P=0.035) and R1 resection (P<0.001). Less patients in the underweight group received adjuvant chemotherapy (P=0.01). Patients in the overweight group had a higher incidence rate of high blood pressure (P<0.001), diabetes (P<0.001) and coronary artery diseases (P<0.001). Moreover, more patients in the overweight group had a lower TNM stage (P=0.003). In the univariated analysis, high BMI was significantly associated with better DSS (P=0.013).

CONCLUSIONS

After adjusting for covariates enrolled for study, high BMI was an independent prognostic factor in weight loss esophageal squamous carcinoma patients.

Staging accuracy of endoscopic ultrasound performed by nonexpert endosonographers in patients with resectable esophageal squamous cell carcinoma: is it possible?

The accuracy of endoscopic ultrasound (EUS) is operator-dependent. According to learning curve study, the accuracy of EUS T-staging for esophageal cancer has been reported to be greater in an investigator who had performed at least 100 EUS examinations. We determined comparative study regarding T-staging accuracy of EUS for esophageal squamous cell carcinoma between expert and nonexpert endoscopic ultrasonographers. We retrospectively identified 73 consecutive patients with esophageal squamous cell carcinoma who underwent EUS and endoscopic mucosal resection, endoscopic submucosal dissection, or surgery. EUS was performed by expert (Group 1) and nonexpert (Group 2) endoscopic ultrasonographers in multitertiary hospitals. Groups 1 and 2 were 37 and 36 patients during 2005-2011, respectively. Forty-two patients (57.5%) of the overall patients underwent surgical exploration. Correct endoscopic ultrasonographic T-staging of Group 1 was observed in 34 (91.9%) patients, while that of Group 2 was observed in 26 (72.2%) patients. And there was significant difference in correct endoscopic ultrasonographic T-staging between Group 1 and Group 2 (P = 0.035). The incorrect endoscopic ultrasonographic T-staging of Group 1 were three cases that were overstaging (8.1%), but in Group 2 there were seven overstaging (19.4%) and three understaging (8.3%). There was no significant difference in overstaging or understaging of incorrect endoscopic ultrasonographic T-staging between Group 1 and Group 2 (P = 0.528). This study first provides evidence that endoscopic ultrasonographic T-staging of nonexpert endoscopic ultrasonographers was inferior to be correct, compared with that of expert endoscopic ultrasonographers. EUS staging for esophageal cancer should be performed by expert endoscopic ultrasonographers to provide appropriate management strategy.

Connective tissue growth factor expression in precancerous lesions of human esophageal epithelium and prognostic significance in esophageal squamous cell carcinoma

Connective tissue growth factor (CTGF, CCN2), a secreted protein, is involved in the development and progression of esophageal squamous cell carcinoma (ESCC). However, it remains unclear how CTGF expression affects the progression of ESCC. Our study implicated differences of CTGF protein status in precancerous lesions, and retrospectively examined the associations of CTGF mRNA and protein levels with clinical prognosis in ESCC patients. Here immunohistochemistry and the quantitative real-time real-time reverse transcription polymerase were performed for predicting the CTGF protein status and mRNA levels in ESCC patients, respectively. Different degrees of CTGF protein status presented in normal human esophageal epithelium and precancerous lesions, and CTGF protein was highly expressed in ESCCs. Survival analysis showed that CTGF protein status was significantly related to poor survival of ESCC patients (P= 0.024), while no significant difference was observed between CTGF mRNA levels and the survival of ESCC patients (P= 0.196). Multivariate Cox analysis demonstrated that CTGF protein status was the independent factor in prognosis of ESCC patients. In that way, CTGF protein status might elevate the progression of ESCC, and would be significant for the diagnosis of precancerous lesions or early ESCC.

Comparative study of the N-linked oligosaccharides released from normal human esophageal epithelium and esophageal squamous carcinoma

N-Linked sugar chains of normal human esophageal epithelium and esophageal squamous carcinoma were quantitatively released as oligosaccharides from their membrane preparations by hydrazinolysis. After being fractionated by serial lectin column chromatography using concanavalin A-Sepharose and Datura stramonium agglutinin-Sepharose, their structures were elucidated by exoglycosidase digestion in combination with methylation analysis. Both normal epithelium and esophageal carcinoma contained bi-, tri- and tetraantennary oligosaccharides as well as high mannose-type oligosaccharides. Interestingly, carcinoma had about 1.6 times larger amounts of tri- and tetraantennary oligosaccharides with the GlcNAc beta 1----4Man alpha 1----and/or the GlcNAc beta 1----6Man alpha 1----linkages than normal epithelium. Tri- and tetraantennary oligosaccharides with N-acetyllactosamine repeating units (the Gal beta 1----4GlcNAc beta 1----3Gal beta 1----4GlcNAc group) were also increased in carcinoma. These data indicated that the altered glycosylation of proteins previously found in transformed rodent cells also occurs widely in human esophageal carcinoma.